Method for imparting flame resistance to fibrous materials

ABSTRACT

METHOD FOR IMPARTING FLAME RESISTANCE TO FIBROUS MATERIALS IS PROVIED COMPRISING APPLYING TO SAID MATERIALS A COMPOUND HAVING THE STRUCTURAL FORMULA: (H-C(-X)=C(-X)-CH2-O-)3-P=O WHEREIN EACH X CAN BE INDEPENDENTLY CHLORO OR BROMO OR WHEN TAKEN TOGETHER CAN FORM A BOND, AND THE SUM OF CHLORINE AND BROMINE ATOMS IN THE COMPOUND IS AT LEAST TWO.

United States Patent m US. Cl. 117--136 8 Claims ABSTRACT OF THE DISCLOSURE Method for imparting flame resistance to fibrous materials is provided comprising applying to said materials a compound having the structural formula:

wherein each X can be independently chloro or bro-mo or when taken together can form a bond, and the sum of chlorine and bromine atoms in the compound is at least two.

This invention relates to a method for imparting flame resistance to fibrous materials. More particularly, the invention relates to the use of halogenated tripropargyl phosphates as flame retardants for fibrous materials.

Most fibers, whether synthetic or natural, and the fabrics made therefrom are quite flammable. The dangers posed by potentially flammable fabrics in the home or on the person have resulted in a quest for effective flame retarding agents which can be readily applied to such fibrous materials. Additionally, it is considered desirable that the presence of a flame retardant in a fabric impart to such fabric the ability to immediately extinguish combustion in the absence of flame thereby eliminating the presence of a potentially dangerous afterglow upon removal of the flame.

Accordingly, it is an object of the present invention to provide effective flame retardants for fibrous materials.

It is another object of the present invention to provide flame retardants which are so effective as to permit no sustained combustion in the absence of flame.

These as well as other objects are accomplished by the present invention which provides a method for imparting flame resistance to fibrous materials comprising applying to said materials a compound having the structural forwherein each X can be independently chloro or bromo or when taken together form a bond, each X can be a halogen radical or when taken together can form a bond, and the sum of X and X atoms in the compound is at least two.

The flame retardants of the present invention are readily prepared by halogenation of tripropargyl phosphate. Most conveniently, the tripropargyl phosphate is dissolved in a halogenated hydrocarbon solvent such as carbon tetrachloride, chloroform, methylene chloride, trichloroethylene, perchloroethylene and the like and a gaseous or liquid halogen is added to the solution. The addition of at least two halogen atoms and preferably, at least four halogen atoms, to the compound is considered necessary to impart flame retardation activity to the compound. Most preferably, the halogens employed are chlorine and bromine; however, in the highly halogenated species, other halogens such as iodine and fluorine can additionally be employed, if desired. The degree of halogena- 3,783,016 Patented Jan. 1, 1974 tion follows the reaction stoichiometry. For example, when one mole of tripropargyl phosphate is reacted with three moles of chlorine, tri(2,3-dichloroallyl) phosphate is obtained. If, however, six moles of chlorine are employed, tri(2,2,3,S-tetrachloropropyl)phosphate is obtained. When halogenation proceeds with less than stoichiometric amounts of halogen present, only partial addition is obtained. Thus, for example, if one mole of tripropargyl phosphate is reacted with tWo moles of chlorine, di-(2,3- dichloroallyl)propargyl phosphate is obtained.

Typical flame retardants encompassed by the present invention are, for example,

tri( 2,2,3,3-tetrachloropropyl) phosphate, tri(2,2,3,3-tetrabromopropyl)phosphate, tri(2,2,3-tribromo-3-chloropropy1)phosphate, tri (2,3-dichloroallyl) phosphate,

tri (2-bromo-3-chloroallyl phosphate,

tri 2-bromo-2-fluoro-3, 3 -dichloropropyl phosphate, tri 2-iodo-2,3,3-tribromopropyl) phosphate, di-(2,3-dibromoallyl)propargyl phosphate, di(2,3-dichloroallyl) propargyl phosphate, 2,3-dichloroallyl-dipropargyl phosphate, 2,3-dibromoallyl-dipropargyl phosphate and the like. The flame retardants of the present invention which contain unsaturated moieties within the molecule have been found to be more hydrolytically stable than the fully saturated species and thus can be employed to advantage in fabrics which undergo laundering.

The flame retardant compositions of the present invention can be applied to fibers and fabrics in any suitable inert vehicle. Generally, these compounds are soluble in halogenated hydrocarbons such as carbon tetrachloride, chloroform, methylene chloride, trichloroethylene, perchloroethylene and the like as well as other non-aqueous solvents such as tetrahydrofuran. Solutions or dispersions containing the flame retardant compositions of the present invention in concentrations ranging from about 5 to about 10 percent by weight can be suitably employed.

The flame retardant compositions can be applied to fibers and fabrics by any convenient means such as spraying, dipping, immersing, padding and the like. If desired, the flame retardant compositions can be admixed with synthetic polymeric materials and can be co-extruded therewith to form fibers exhibiting flame retardation. Generally, it is considered preferable to impart from about 5 to about 20% by Weight on a dry basis of the flame retardant composition to the fibers or fabrics being treated to obtain effective flame retardation.

Both synthetic and natural fibers and the fabrics made therefrom can be treated in accordance with the present invention. Typical fibers which can be treated are, for example, cotton, wool, silk, nylon, rayon, polyesters and the like.

It has been found that when the halogenated tripropargyl phosphate compositions of the present invention are applied to fibers and fabrics in the manner described hereinabove, the resulting materials will not support combustion and will only char in the presence of an open flame. Upon removal of the flame, burning immediately ceases without an afterglow.

The following examples further define, describe and compare methods or preparing and employing the flame retardant compositions of the present invention. Parts and percentages are by weight unless otherwise indicated.

EXAMPLE I To a solution of 10.5 g. (0.05 mole) of tripropargyl phosphate in 1-00 ml. carbon tetrachloride was added dropwise, with cooling, 48 g. (0.3 mole) bromine. In the initial stages of addition, bromine was taken up rapidly as shown by the disappearance of the bromine color. After completion of the addition, the reaction mixture was stirred at room temperature for seventeen hours. A solid precipitated. This was filtered and Washed with carbon tetrachloride and vacuum dried. It weighed 28.3 g. and melted at 140l54 C. (48% yield). After recrystallization from chloroform the solid melted at 150153 C. This solid Was identified as OP OCH CBr CBr H Analysis.Calcd. for C H Br O P (percent): C, 9.24; H, 0.77; Br, 81.88; P, 2.64. Found (percent): C, 9.45; H, 0.91; Br, 82.80; P, 2.80, 2.80.

Nuclear magnetic resonance analysis (relative to tetramethylsilane): 6.15 p.p.m. (singlet) Intensity 1 CBr H; 4.8 p.p.m. (doublet) Intensity 2 OCH EXAMPLE II The procedure in Example I was repeated using 42.4 g. (0.2 mole) tripropargyl phosphate, 120 ml. (2.3 moles) bromine and 500 ml. carbon tetrachloride. In this manner, 200 g. (76%) of OP(OCI-l CBr CBr H) was isolated.

EXAMPLE III To a solution of 21.2 g. (0.1 mole) tripropargyl phos phate in 100 ml. carbon tetrachloride was added, with cooling, 16 ml. (0.3 mole) bromine. After stirring for 2 hours at ambient temperature, no solid had formed. The solvent was removed under vacuum. There remained 64.8 g. (92%) of liquid identified as:

OP(OCH CBr==CBrH) The IR did not contain a triple bond absorption at 2120 cmf but did had a medium C=C absorption at 1610 cmr EXAMPLE IV To a solution of 21.2 g. (0.1 mole) tripropargyl phosphate in 100 ml. carbon tetrachloride was added dropwise, with cooling, 11 ml. (0.2 mole) bromine. The solution was allowed to warm to room temperature and the solvent removed under vacuum. There was obtained 45.6 g. of a brown oil which was identified as:

EXAMPLE V Into a cold solution of 21.2 g. (0.1 mole) tripropargyl phosphate in 100 ml. carbon tetrachloride was passed 49.5 g. (0.7 mole) chlorine gas over the course of two hours. The solution was allowed to stand overnight at ambient temperature. The solvent was removed under vacuum leaving 63.7 g. (100%) of OP (OCH CCl CCI H) 3 EXAMPLE VI The procedure in Example V was repeated using 21.2 g. (0.1 mole) tripropargyl phosphate, 21.3 (0.3 mole) chlorine gas in 100 ml. carbon tetrachloride. There was obtained 42.5 g. (100%) of OP(OCH CCl=CClH) EXAMPLE VII The procedure in Example V was repeated using 21.2 g. (0.1 mole) tripropargyl phosphate, 14.2 g. (0.2 mole) chlorine gas in 100 ml. carbon tetrachloride. There was isolated 35.4 g. (100%) of EXAMPLE VIII A solution of 5 g. of OP(0CH CBr CBr H) prepared as described in Example II, 45 g. tetrahydrofuran, 32.5 g.

EXAMPLE IX Employing the procedure described in Example VIII, solutions were prepared of the following compounds:

These solutions were respectively charged to aerosol bottles and sprayed onto cotton broadcloth to a 17% dry weight pick up. Each of the cloths so treated charred when held in the flame of a burning match. The cloths each ceased burning immediately upon removal of the flame. In no instance was an afterglow observed.

Although specific materials and conditions are set forth in the above exemplary processes in making and using the fiame retardant compositions of this invention, these are merely intended as illustrations of the present invention. Various other tripropargyl phosphates, vehicles, modes of application, fibers and fabrics such as those listed above may be substituted in the examples with similar results.

Other modifications of the present invention will occur to those skilled in the art upon a reading of the present disclosure. These are intended to be included with the scope of this invention.

What is claimed is:

1. Method for imparting flame resistance to fibrous materials comprising applying to said materials a compound having the structural formula:

wherein each X can be independently chloro or bromo or when taken together can form a bond, and the sum of chlorine and bromine atoms in the compound is at least tWO.

2. Method as defined in claim 1 wherein the compound is applied in combination with an inert vehicle and the resulting material dried.

3. Method as defined in claim 2 wherein the compound is present in the inert vehicle in concentrations ranging from about 5 to about 10 percent by weight.

4. Method as defined in claim 1 wherein the compound is applied to the fibrous material in sufi'icient quantities to impart thereto from about 5 to about 20% by weight of said compound on a dry basis.

5. Method as defined in claim 1 wherein the compound is tri(2,3-dibromoallyl)phosphate.

6. Method as defined in claim 1 wherein the compound is tri(2,3-dichloroallyl) phosphate.

7. Method as defined in claim 1 wherein the compound is di(2,3-dibromoallyl)propargyl phosphate.

8. Method as defined in claim 1 wherein the compound is di(2,3-dichloroallyl)propargyl phosphate.

(References on following page) 6 OTHER REFERENCES Miles et a1., Textile Research Journal, A Laboratory Study April 1969, pp.357362, vol. 39, No. 4.

5 References Cited UNITED STATES PATENTS 12/ 1953 Paist et a1 X Cherbuliez, Helvetica Chimica Acta, vol. 47, pp. 2098- 9/1971 DiPietro 117-136 5 2105 (1964). 2/1963 Farm 106-15 X WILLIAM D. MARTIN, Primary Examiner FOREIGN PATENTS H. I. GWINNELL, Assistant Examiner 9/1969 Great Britain 117-136 10 us. 01. X.R. 12/1963 France 260861 117-138.8 F, 138.8 N, 141, 143111, 144; 252-8.1, 264- 2/1957 France 260-8 61 211 3 3 UNITED STATES PATENT OFFlCE CERIFECATE @F CG f ECTION Patent No. ;5,783,()l6 Dated May 21, 1

Inventor(s) David I, Randall et al It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

I- In the heading line 4 after, "both of Easton, i

Pennsylvania, 18042", please insert '-assignors to GAF Corporation, New York, New York-.

Signed and sealed this 22nd day of October 1974.

(SEAL) Attest:

MCCOY M. GIBSON JR. c. MARSHALL DANN Attesting Officer comis ionez; of Patents *y l L. '?f-" if .1

3 3 UNITED STATES PATENT OFFlCE CERTIFICATE @F CGRRECTION Patent No: ,783,Ol6 Dated May 2l, l

Invmnwr(s) David I Randall et al It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

r In the heading line 4 after, "both of Easton, 1

Pennsylvania, 18042", please insert assignors to GAF Corporation, New York, New York.

Signed and sealed this 22nd day of October 1974.

(SEAL) Attest:

MCCOY M. GIBSON JR. c. MARSHALL DANN Attesting Officer Commis ioner of Patents *y l L. '?f-" if .1

w UNITEDSTATES PATENT 0FFICE CERTIFI C ATE' OF CORRECTIDN Patent No. 3, 78 3 016 Dated Ma '121, r971 Inventor(s David Randall et It is certified that erro r appears in the above-{identified patent and thatsaid Letters Pa tenpare hereby corrected as shown below:

' In the heading line 4 after, "both of Easton,

Pennsylvania, 18042", please insert -assiqnors to GM Corporation, New York, New York-.

Signed and sealed this 22nd day of October 1974;

(SEAL) Attest M a v MCCOY M. GIBSON JR. 9 x e CQMARSH'ALL DANN Attesting Officer Comissioner of Patents 

